Floyd Mayweather Jr. and Robert Guerrero exchange punches in the first round during a WBC welterweight title fight. / Isaac Brekken, AP

by Jon Saraceno, USA TODAY Sports

by Jon Saraceno, USA TODAY Sports

"Boxing is like jazz,'' said the former heavyweight champion. "The better it is, the less people appreciate it.''

Maybe that was one reason why some of the 15,688 fans at the MGM Grand Garden Arena who were booing felt somewhat unfulfilled Saturday evening after Floyd Mayweather Jr. gave challenger Robert Guerrero a case of the blues. The undefeated world welterweight champion (44-0, 26 KOs) didn't even bother to resort to improvisation as he coasted to a unanimous 12-round decision despite injuring his right hand midway through the fight.

All three judges scored the fight 117-111 for Mayweather, a testament to how easy he made it look. And that's after not fighting for a year.

Fight fans who admire Mayweather's peerless ring rhythm won't be able to enjoy him long, and the champion reiterated that after his victory.

"I've got five more fights and I'm through with the sport,'' said Mayweather, 36, who was paid a guaranteed $32 million for the fight with a potential upside that could reach upwards of $40 million depending upon ticket and pay-per-view TV sales.

Mayweather still plans to fight in September, possibly against undefeated Canelo Alvarez.

Mayweather likes to say that every opponent has a game plan but his challenger joined a blossoming list of busted blueprints and broken dreams. As his own promoter, Mayweather might even make a better matchmaker than he does a fighter. Guerrero, two beats slower and totally outclassed, was made to order for the champion's superior speed and ring savvy. The challenger was badly cut in the eighth around above his left eye from Mayweather's quick, slashing punches.

Despite his impressive performance, the champion would not be drawn into a comparison to past greats, including both Sugar Rays (Robinson and Leonard), Roberto Duran and Thomas Hearns, who attended the fight.

"I take my hat off to any fighter who paved the way for me,'' Mayweather said. "I'm not in their era. . . . I'm in my era.''

Using effective lateral movement and explosive lead right hands, the 36-year-old champion and former Olympic bronze medalist dominated the bout against his outclassed opponent in his first bout since last May when he pounded out a 12-round decision against Miguel Cotto. In that fight, the champion was hit more than ever before in his 17-year career.

A month after defeating Cotto, Mayweather went to jail for two months, most of it in solitary confinement,on a domestic assault charge.

"They said I was losing my legs,'' Mayweather said. "I showed the world I can still box. I showed them I'm still fast.''

Before the bout, "Dad said, 'I tell you what's going to get him - right hands all day','' he said of his father-trainer, Floyd Sr.

Mayweather pot-shotted Guerrero at will as the challenger fruitlessly tried to box the champion from the outside when he wasn't using rough-house tactics on the inside. Nothing worked - even when Mayweather leaned on the ropes and tried to lure in his challenger.

"Always when we take a long time off, I wonder, 'Damn, do I still got it?' Mayweather said. "Tonight I was the better man.''

The challenger, a 30-year-old native of Gilroy, Calif., nicknamed "The Ghost,'' had not lost a fight since 2005. Guerrero is 31-2-1.

"Floyd's a great defensive fighter,'' Guerrero said.

The bout was Mayweather's first since May of 2012 when he pounded out a 12-round decision against Miguel Cotto. In that fight, the champion was hit more than ever had been in his 17-year career. Reunited with his father, the champion was far more elusive.

"I had to bring the defensive master back, my father,'' said the champion.

Because of internal strife within the family, the father-son team had not worked together for a fight since 2000 when Floyd Sr. was replaced by his brother, Roger. The champion asked his father to return to his side only last month.

"I told him we ain't gonna take no more punches,'' Floyd Sr. said he told his son when he rejoined.